Vibrant ultramarine or warm cobalt? Tasty blueberry? Clear aquamarine maybe? Topaz? Sapphire? Steel or teal? Persian or parisian? ...or indian indigo? Noble royal blue shade? Simple denim? Phthalo? Cyjan? Aquamarine... decide!
I'm having fun with 'blue-analysis' on my tumblr here: design traveller. Have you discovered this blogging platform yet? If you are tumbling as well, let me know :)